Haie Hill Tunnel
in the Forest of Dean
Originally built for the Bullo Pill Railway (tramway). Engineer: John Hodgkinson. Contractor Robert Tipping. At 1083 yards, it is said to have been the world's longest when opened in 1810. The line was taken over by the South Wales Railway in 1851. Enlarged by I K Brunel to take broad gauge track in 1854. Changed to standard gauge in 1872. Closed in 1967.
Sources of Information
-  'Forgotten Relics of an Enterprising Age' website, Haie Hill Tunnel page